Is your gateway configured for remote access VPN?
Please refer:
sk60773: [RST, ACK] response to TCP/264
sk132712: Vulnerability scan shows ports 18231 and 264 open under LISTEN mode when using TLS1.0 and TLS1.1 - reference CVE-2000-1201
sk69360: Check Point response to SecuRemote Topology Service Hostname Disclosure
sk62692: Ports used on Security Gateway for SecureClient and Endpoint Security VPN
If you have no plans to leverage Check Point remote access disabling this global option may also work for you:
CCSM R77/R80/ELITE